<template>
  <div class="app-container">
    <el-button
      :loading="downloadLoading"
      style="margin-bottom: 20px"
      type="primary"
      icon="el-icon-document"
      @click="handleDownload"
      >Export
    </el-button>

    <el-table
      ref="multipleTable"
      v-loading="listLoading"
      :data="list"
      element-loading-text="Loading"
      border
      fit
      highlight-current-row
    >
      <el-table-column align="center" label="Id" width="95">
        <template slot-scope="scope">
          {{ scope.$index }}
        </template>
      </el-table-column>
      <el-table-column label="Main Information" align="center">
        <el-table-column label="Title">
          <template slot-scope="scope">
            {{ scope.row.title }}
          </template>
        </el-table-column>
        <el-table-column label="Author" width="110" align="center">
          <template slot-scope="scope">
            <el-tag>{{ scope.row.author }}</el-tag>
          </template>
        </el-table-column>
        <el-table-column label="Readings" width="115" align="center">
          <template slot-scope="scope">
            {{ scope.row.pageviews }}
          </template>
        </el-table-column>
      </el-table-column>
      <el-table-column align="center" label="Date" width="220">
        <template slot-scope="scope">
          <i class="el-icon-time" />
          <span>
            {{ scope.row.timestamp | parseTime("{y}-{m}-{d} {h}:{i}") }}
          </span>
        </template>
      </el-table-column>
    </el-table>
  </div>
</template>

<script>
import { parseTime } from "@/libs/utils";
export default {
  name: "MergeHeader",
  data() {
    return {
      list: [],
      listLoading: true,
      downloadLoading: false,
    };
  },
  created() {
    this.fetchData();
  },
  methods: {
    fetchData() {
      this.listLoading = true;
      this.$apis.article.fetchList(this.listQuery).then((response) => {
        this.list = response.data.items;
        this.listLoading = false;
      });
    },
    handleDownload() {
      this.downloadLoading = true;
      import("@/vendor/Export2Excel").then((excel) => {
        const multiHeader = [["Id", "Main Information", "", "", "Date"]];
        const header = ["", "Title", "Author", "Readings", ""];
        const filterVal = [
          "id",
          "title",
          "author",
          "pageviews",
          "display_time",
        ];
        const list = this.list;
        const data = this.formatJson(filterVal, list);
        const merges = ["A1:A2", "B1:D1", "E1:E2"];
        excel.export_json_to_excel({
          multiHeader,
          header,
          merges,
          data,
        });
        this.downloadLoading = false;
      });
    },
    formatJson(filterVal, jsonData) {
      return jsonData.map((v) =>
        filterVal.map((j) => {
          if (j === "timestamp") {
            return parseTime(v[j]);
          } else {
            return v[j];
          }
        })
      );
    },
  },
};
</script>